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Rapid prototyping photolithography of a thiolene-based resin was used to fabricate microfluidic devices stable to aliphatic and aromatic organic solvents. The swelling of the cross-linked polymer matrix in various organic solvents was quantified, and the solvent resistance properties of these microfluidic devices are described. Discrete droplets of hexanes and toluene of uniform size were generated in microfluidic devices inside a water matrix containing SDS surfactant (SDS = sodium dodecyl sulfate). Variation of water and organic flow rates in the fluidic channels was used to control droplet size and separation. Droplet composition could be controlled by varying flow rates of two joined organic streams. Organic-phase synthetic reactions within the droplets were demonstrated with the bromination of alkenes inside benzene droplets.

The reaction of (Et3P)2Pd(μ-S)Ge[N(SiMe3)2]2 (2) with paraformaldehyde under photolytic conditions results in the insertion of formaldehyde into the Pd−Ge bond, with bond cleavage, to give (Et3P)2Pd(μ-S)(μCH2O)Ge[N(SiMe3)2]2 (3). Subsequent addition of CO to 3 results in migratory insertion into the Pd−C bond, followed by rapid reductive elimination to regenerate the Pd⁰ metal center and give a unique five-membered organic heterocycle, Ge[N(SiMe3)2]2SC(O)CH2O (6). The X-ray crystal structure of the dppe (dppe = bis(diphenylphosphino)ethane) derivative of 3, (dppe)Pd(μ-S)(μCH2O)Ge[N(SiMe3)2]2 (4), is reported.

The synthesis of three novel Pd germylene complexes is reported. (Ph3P)2PdGe[N(SiMe3)2]2 (1) was synthesized by ligand substitution of (Ph3P)4Pd, whereas (Et3P)PdGe[N(SiMe3)2]2 (2) and {dppePdGe[N(SiMe3)2]2}2 (3b) (dppe = (diphenylphosphino)ethane) were synthesized by photolytic reduction of their corresponding phosphine oxalato complexes followed by addition of the germylene ligand. In solution, 3b exists in equilibrium with the monomeric dppePdGe[N(SiMe3)2]2 (3a). The germylene ligand of 2 was found to be 1 order of magnitude more labile than the analogous Pt system and 2 orders of magnitude less labile than the analogous Ni system. The reactivity of these new palladium germylenes toward O2 is described.

Ge[CH(SiMe3)2]2 reacts with benzophenone to form a conjugated triene. Wilkinson's catalyst, Rh(PPh3)3Cl, is an effective precatalyst for the isomerization of one double bond and hydrogenation of a second double bond of this triene. This reaction demonstrates that germylene activation of the phenone moiety yields reactive double bonds amenable to catalytic transformation, even with bulky catalysts such as the presumed active form of Wilkinson's catalyst, Rh(PPh3)2Cl.